With the development of science and technology, more and more people prefers to travel by air. However, traveling by air brings many security risks, while saving time and improving efficiency for passengers.
Typically, when traveling by air, passengers will be required to power off electronic devices such as mobile phones. A mobile phone is not allowed to be used on a plane, because radio waves emitted by the mobile phone may interfere with air-ground communications and affect flight safety.
Currently, many mobile phones have the function of power-off alarm. With an alarm preset in a mobile phone, it can power on the mobile phone at a preset time and ring even if the mobile phone is in a powered-off state. As such, important alerting alarms can be prevented from being missed in case the mobile phone has been powered off by a user. However, if the user is travelling by air, the activation of the power-off alarm will power on the mobile phone, thus, bringing security risks.